Creating an additional trade period on the eve of the AFL season could bring immense upside for injury-hit clubs, according to former Carlton list manager Stephen Silvagni.

The 2021 season doesn't conclude until Saturday night but the off-season frenzy has already begun in earnest, with several players requesting trades.

The AFL introduced free agency at the end of the 2012 season, while it has since given the green light to trading future draft selections - and trading live picks on draft night.

But exchanging players is only possible during the speculation-laden period following the grand final.

The push for a mid-season draft, which was introduced in 2019, was driven by a school of thought that injury-decimated clubs should be able to top up their list in a time of great need.

Silvagni, proposing a second trade period that would fall "a week or two before the season starts", used similar logic.

"Players get stress fractures and serious injuries in pre-season. Clubs can lose a ruckman, a couple of forwards or whatever it is," Silvagni told AAP at the launch of AFL Trade Radio.

"I'd certainly like to see something put forward, to see how that could look before the start start of the year.

"It'd create interest in footy as well, keep AFL in the papers, and it'd be good for footy clubs."

Silvagni conceded the salary cap, which forms part of clubs' actions in post-season wheeling and dealing, was a complicating factor.

"Most clubs' final player payments are put in before that time. So that's one hurdle that clubs and the AFL would need to clear," he said.

"It's just something to look at.

"I'm not saying it should happen but is there a chance that something can happen in that period.

"We should keep looking at it, keep throwing up suggestions. That's always a good thing."